821 B
821 B
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
5900f43e1000cf542c50ff50 | Problem 210: Obtuse Angled Triangles | 5 | 301852 | problem-210-obtuse-angled-triangles |
--description--
Consider the set S(r) of points (x,y) with integer coordinates satisfying |x| + |y| ≤ r.
Let O be the point (0,0) and C the point (r/4,r/4).
Let N(r) be the number of points B in S(r), so that the triangle OBC has an obtuse angle, i.e. the largest angle α satisfies 90°<α<180°.
So, for example, N(4)=24 and N(8)=100.
What is N(1,000,000,000)?
--hints--
euler210()
should return 1598174770174689500.
assert.strictEqual(euler210(), 1598174770174689500);
--seed--
--seed-contents--
function euler210() {
return true;
}
euler210();
--solutions--
// solution required